As shown in FIG. 1, an LCD panel generally includes a lower color film (CF) substrate 13, a thin-film transistor (TFT) substrate 11, a liquid crystal 12, filter(s) 142, an upper polaroid (not shown in the figure) and the like. The liquid crystal 12 is arranged between the TFT substrate 11 and the CF substrate 13. The TFT substrate 11 and the CF substrate which are in contact with the liquid crystal are coated with a layer of oriented film 14, respectively. The oriented films 14 are used for limiting the oriented state of the molecules of the liquid crystal 12. After the liquid crystal 12 is filled between the TFT substrate 11 and the CF substrate 13, the bonding sealing is accomplished by a frame adhesive 15. A lower polaroid is bonded to the bottom surface of the TFT substrate 11. An upper polaroid is bonded to the top surface of the CF substrate 13. Thus, an LCD panel is finally formed.
The oriented films 14 are coated on the corresponding substrates by a printer. The oriented films 14 are covered on the effective display areas of the LCD panel. Take the CF substrate as shown in FIG. 2 as an example, the A.A area is an effective display area, and the oriented film 14 should cover the A-A area, but the oriented film 14 can not cover the position coated with frame adhesive 15. When applying a voltage to the LCD panel, the frame adhesive 15 can produce impurities which permeate into the effective display area 142 and become liquid crystal pollutants. The liquid crystal pollutants are adsorbed on the oriented film 14 so that the pixel here can produce stains or non-uniform display.